Machine learning-implemented inkjet processing for generation of three-dimensional relief on tiles

ABSTRACT

A technique is described for the application of three-dimensional (3D) relief to a substrate such as a ceramic tile using digital inkjet technology. A computer system receives information defining a relief pattern for forming the 3D relief using a digital inkjet printer. From the information, a feature vector is extracted comprising one or more features describing the 3D relief. A machine learning model is used to generate control commands based on the feature vector. The machine learning model is trained to generate the control commands to configure the digital inkjet printer to apply binder ink to a first region of a surface of the substrate. The applied binder ink is configured to form a protective layer over the first region of the surface of the substrate. The digital inkjet printer is configured to apply solvent ink to the surface of the substrate.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation-in-part of U.S. patent applicationSer. No. 18/304,171, filed on Apr. 20, 2023, which is a continuation ofU.S. patent application Ser. No. 17/085,069, filed on Oct. 30, 2020, nowU.S. Pat. No. 11,633,972, which is a divisional of U.S. patentapplication Ser. No. 16/154,525, filed on Oct. 8, 2018, now U.S. Pat.No. 10,836,195, and which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present disclosure generally relates to processing techniques forforming textured relief in substrates such as ceramic tiles.

BACKGROUND

Tiles have a wide range of applications as building materials (e.g., forflooring) or as decorative objects. Various processes have beendeveloped to apply three-dimensional (3D) relief to tiles, for example,to improve functionality and/or add ornamentation. Existing approachesfor adding 3D relief to a tile include digital processes such as:additive processes whereby ceramic material is applied to the surface ofa tile, subtractive-like processes whereby a ceramic fluxing material isapplied to the glazed surface of a tile, and wax-resist processeswhereby a wax-like material is applied to the surface of a tile prior toglazing, as well as analog stamping processes whereby tile body powdersare pressed in a mold.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a flowchart illustrating a first example process forapplying a three-dimensional (3D) relief to a substrate using digitalinkjet technology.

FIGS. 2A-2C show a sequence of illustrative diagrams depictingprocessing of a first substrate according to the process of FIG. 1 .

FIG. 3 shows a flowchart illustrating an example process that can beapplied to the substrate after the 3D relief has been formed.

FIGS. 4A-4C show a sequence of illustrative diagrams depictingprocessing of the first substrate according to the process of FIG. 3 .

FIG. 5 shows a flowchart illustrating a second example process forapplying a 3D relief to a substrate using digital inkjet technology.

FIGS. 6A-6D show a sequence of illustrative diagrams depictingprocessing of a second substrate according to the process of FIG. 5 .

FIGS. 7A-7C show a sequence of illustrative diagrams depictingprocessing of the second substrate according to the process of FIG. 3 .

FIG. 8 is a diagram of an example automated production system that canbe configured to implement the introduced technique for applying 3Drelief to a substrate using digital inkjet technology.

FIG. 9 is a block diagram of an example computing system as may be usedto implement certain features of some of the embodiments.

FIG. 10 is a block diagram that illustrates an example machine learningsystem that can implement aspects of the present technology.

FIG. 11 is a block diagram that illustrates an example of a computersystem in which at least some operations described herein can beimplemented.

FIG. 12 is a flowchart that illustrates an example process forgenerating three-dimensional reliefs on tiles using inkjet printing.

FIG. 13 is a block diagram illustrating a perspective view of a printingsystem, in accordance with one or more embodiments.

FIG. 14 is a block diagram illustrating a side view of a printingsystem, including a printer head and a light source, in accordance withone or more embodiments.

DETAILED DESCRIPTION

Overview

Existing approaches for adding 3D relief to tiles have severaldrawbacks. For example, current digital processes (additive,subtractive, etc.) result in subtle, poorly defined relief effects dueto technological limitations. Further, existing digital processesinvolving subtractive methods (i.e., sinking ink) typically involve theuse of heavy metals that are both toxic and significantly more expensiveto generate. Existing analog stamping processes can result in morewell-pronounced 3D relief patterns as compared to existing digitalprocesses. However, existing analog stamping processes allow for limitedvariation in relief patterns since every stamped tile will have the samerelief pattern until the stamping mold is changed. Generating newstamping models is costly and changing between stamping molds duringprocessing is both time and labor intensive.

Introduced herein is technique for applying 3D relief to substrates suchas tiles using a digital inkjet technology that addresses theabove-mentioned problems with existing approaches. In an exampleembodiment, the introduced technique includes applying binder ink to aportion of the surface of a substrate (e.g., a tile) using a digitalinkjet process. This binder ink forms a barrier layer that protects theportion of the surface of the substrate. Next, a brushing process isapplied to remove unprotected portions of the substrate, thereby formingthe 3D relief in the substrate.

The incorporation of inkjet technology in the introduced techniqueeliminates the need for expensive stamping molds while still maintainingthe durability of the surface of the substrate unlike existing digitalprocesses. For production efficiency, the introduced technique avoidsthe added time and labor needed to stop production to change reliefdesigns, reducing production costs and opens more design variability,for example, to mimic the look of “natural” materials. Further, theintroduced technique allows for the matching of relief patterns todigitally printed color designs later in the production process, therebyimproving design quality and enabling designers to diversify theirproduct offerings.

Terminology

Substrate: A “substrate” refers to any material upon which the disclosedtechnique for forming a 3D relief can be applied. In exampleembodiments, the substrate includes an absorbent layer of material uponwhich ink can be applied using an inkjet process and that can beremoved, for example, using a physical process such as brushing.Examples of substrates include hydraulically pressed ceramic green tile(single or double charged), glazed surface, or any other preparationwith similar characteristics. The substrate includes at least one (e.g.,a top surface) surface upon which the disclosed technique for reliefformation is applied. In some embodiments, the surface of the substrateis flat or at least substantially flat (i.e., little change in elevation(e.g., on the order of ±1 millimeter) relative to the length and/orwidth of the surface of the substrate) although the surface need not beflat in all embodiments.

Relief: Relief generally refers to a difference in elevation on asurface. As used herein, the terms “relief” or “3D relief” may refer tothe difference in elevation of the surface of the substrate resultingfrom the disclosed technique whereby material is removed from certainregions of the surface of the substrate. The pattern formed in thesurface of the substrate by the removal of material from certain regionsof the substrate is referred to herein as a “relief pattern.” As will bedescribed in more detail, the relief pattern can be defined based on adigital image. The relief formed in the substrate may exhibit variouscharacteristics such as depth and gradient. The depth of the relief maybe defined as a vertical distance relative to the original surface ofthe substrate. For example, the disclosed technique may involve removingmaterial up to a particular depth relative to the original surface ofthe substrate. The relief may also exhibit a gradient based on a ratiobetween a horizontal distance and a difference in elevation between twopoints. The gradient may exhibit a constant slope or a slope that variesover the horizontal distance between the two points.

Inkjet Printing: Inkjet printing generally refers to the process ofrecreating a digital image by propelling droplets of ink fluid onto asubstrate. Methods of inkjet printing include continuous inkjet (CIJ),thermal drop-on-demand (DOD) and piezoelectric DOD.

Binder Ink Fluid: Binder ink fluid or simply “binder ink” refers to anyfluid that can function to protect material of the substrate (e.g.,substrate powders) when applied. In some embodiments, the binder ink isa fluid that can be applied to the substrate using an inkjet printing toform a protective layer on the substrate. In the context of ceramic tilesubstrate, the binder ink is used to strengthen and protect the ceramicpowders in regions of the surface of the tile where it is applied. Thebinder ink fluid may comprise a resin/polymer aqueous-based orsolvent-based solution with properties suitable for use by an inkjetprinter. Depending on the specific implementation, the binder ink fluidmay include or be used in combination with other materials such ascurable materials (e.g., ultraviolet (UV), thermal, two-part, etc.), lowmelting point waxes, polymers, dispersed particles, or silanes. Thebinder ink fluid can be substantially transparent or may include a dyeor some other pigment to allow the placement of binder ink fluid on thesubstrate to be observed after application. In a ceramic process, anydye or pigment in the binder ink fluid may be organic-based to allow forremoval through incineration during the kiln firing process.

Solvent Ink Fluid: Solvent ink fluid or simply “solvent ink” can beapplied, for example using an inkjet process, on top of the protectivelayer formed by the binder ink, to produce gradient 3D reliefformations. When applied, the solvent ink forces the binder ink intosubstrate. The solvent ink fluid may comprise any type of solutioncapable of temporarily dissolving the resin (or other material) used forthe binder ink. Solvent ink fluids for aqueous and polar-solvent binderinks may comprise, for example, blends of any one or more of thefollowing example solvents: water, ethylene glycol, glycerin, ethyleneglycol ethyl ether, diethylene glycol ethyl ether, propylene glycol,dipropylene glycol, dipropylene glycol methyl ether, tripropyleneglycol, propylene glycol methyl ether, n-methyl-2-pyrrolidone, methanol,ethanol, isopropanol, n-propanol, butanols, ethyl lactate, acetone andother polar solvents. Solvent ink fluids for mid- to non-polar binderinks may comprise, for example, blends of any one or more of thefollowing solvents: aliphatic hydrocarbon distillates, ethyl acetate,propylene glycol butyl ether, dipropylene glycol methyl ether,dipropylene glycol butyl ether, tripropylene glycol methyl ether,ethylene glycol butyl ether, diethylene glycol butyl ether, methyl ethylketone, toluene, xylenes, tetrahydrofuran, methyl amyl ketone,cyclohexanone, and other non-polar solvents.

Brushing: After the binder ink sets, thereby forming a protective layerover the printed regions of the surface of the substrate, a brushingprocess is applied to physically remove material from the unprinted(i.e., unprotected) regions of the surface of the substrate. Thisprocess of removing material from certain regions of the surface of thesubstrate forms the 3D relief.

Glazing: A glaze may be applied as a post-process after forming the 3Drelief according to the disclosed technique. Application of a glaze istypically used in ceramics for decoration (e.g., to add gloss, texture,or color), to seal porous surface, and/or to add an additional layer ofprotection against wear. The glaze may comprise any material suitablefor the underlying substrate and may be applied using known glazingprocesses such as spray, waterfall, or digital inkjet.

Color Printing: Color printing may be applied as a post-process afterforming the 3D relief and/or applying a glaze to add decorative color.Color printing can be applied, for example, using digital inkjetprinting (as described above) or by using analog techniques such asgravure, screen printing, etc.

Firing: Firing, in the context of ceramic processing, generally refersto the process of applying heat to the material (e.g., clay and anyadded glaze) of a “green” substrate to form a final ceramic product. Atypical industrial ceramic tile process involves firing forapproximately 1-2 hours at a temperature between 1030° C. and 1250° C.

Example Processes for Applying 3D Relief to a Substrate Using DigitalInkjet Technology

FIG. 1 is a flowchart illustrating a first example process 100 forapplying 3D relief to a substrate using digital inkjet technology.Certain steps of the example process 100 are described with reference toFIGS. 2A-2C which show a sequence of illustrative diagrams depictingprocessing of a substrate according to the introduced technique. Certainsteps of the example process 100 depicted in FIG. 1 may be performed byone or more components of the automated production system 800 depictedin FIG. 8 and/or the example computing system 900 depicted in FIG. 9 .The process 100 described with respect to FIG. 1 is an example providedfor illustrative purposes and is not to be construed as limiting. Otherprocesses may include more or fewer steps than depicted while remainingwithin the scope of the present disclosure. Further, the steps depictedin example process 100 may be performed in a different order than isshown.

Example process 100 begins at step 102 with receipt of an input whichdefines the relief pattern which will be applied to a substrate such asa ceramic tile. The substrate can include polyvinyl chloride (PVC),polymethyl methacrylate (PMMA), acrylonitrile butadiene styrene (ABS),or luxury vinyl tile (LVT). PVC is a synthetic plastic polymer. PMMA,also known as acrylic, acrylic glass, or plexiglass, is a transparentthermoplastic used in sheet form as a lightweight or shatter-resistantalternative to glass. ABS is a common thermoplastic polymer havingfavorable mechanical properties such as impact resistance, toughness,and rigidity. LVT is a finished flooring material used in commercial andinstitutional applications. LVT is composed of colored PVC chips formedinto solid sheets of varying thicknesses by heat and pressure. Theembodiments disclosed herein can be implemented in the LVT market andfor construction that requires a post-print finishing thermo-laminationor bonding process of digitally printed films to rigid core materials.Additional printing applications using ABS, PVC, and PMMA also benefitfrom the disclosed embodiments, including shower and bath enclosures,automotive interior trim, secure credit cards, and luxury boats andyachts.

The input received at step 102 may include, for example, a digital imageof a design upon which the relief pattern will be based. The digitalimage may comprise any type of data that can be processed by a computerprocessing system (e.g., processing system 900) to define a reliefpattern to be applied to a substrate using the introduced technique. Insome embodiments, the digital image may be a monochrome image of adesign defining a certain area corresponding to the relief pattern to beprinted. In some embodiments, the digital image may be a polychromeimage which defines both the relief pattern to be applied as well ascoloring (e.g., through color inkjet printing) as a post-process afterapplying the relief.

In some embodiments, the input received at step 102 may includeparameters associated with the processes to be applied to the substrate.For example, such parameters may include a type of substrate (e.g.,material type, dimensions, etc.), dimensions of the relief to apply(e.g., depth, gradient, etc.), selections of post-processes to apply(e.g., glazing, color printing, firing, etc.), or any other relevantparameters. Parameters may be input by a user, for example, via acomputing device, or received from other components of an automatedproduction system.

Although not depicted in FIG. 1 , in some embodiments, step 102 mayinclude processing data (e.g., data included in the received inputs) bya computer processing system. For example, step 102 may include imageprocessing to prepare a received digital image for use in defining arelief pattern. As an illustrative example, a digital image including adesign in black against a white background defining a relief pattern maybe processed to invert color values such that the printed portions(i.e., the black portions of the image) define areas of the substratewhich will be protected from removal, for example, by brushing.

Example process 100 continues at step 104 with applying binder ink toform a protective layer over a region of the surface of a substratebased upon the received input. FIG. 2A shows a profile view of asubstrate 200 and FIG. 2B shows a profile view of the same substrate 200with binder ink applied to form a protective layer over a region of thesurface of the substrate 200.

As previously discussed, in some embodiments, the substrate 200 may be aceramic tile. The example substrate 200 depicted in FIGS. 2A-2B ismulti-layered and includes at least a top layer 200 a and a bottom layer200 b. The top layer 200 a may be a double charge layer of a doublecharge vitrified tile. Double charged tiles are typically thicker thanstandard tiles by a few millimeters (mm) making them well suited togenerating relief through subtractive processing. However, a personhaving ordinary skill in the art will recognize that introducedtechnique can similarly be applied to substrates having more or fewerthan two layers. Further, the depth of the top layer 200 a may beexaggerated in FIGS. 2A-2C relative to the depth of the bottom layer 200b for illustrative clarity. In the case of a double charged tile, whichtypically has a total thickness of approximately 5-10 mm, the top layer200 a (or double charge layer) will typically account for approximately10-30% of the total thickness.

As depicted in FIG. 2B, the binder ink can be applied using an inkjetprocess which involves propelling droplets 220 of the binder ink intothe surface of the substrate 200. The droplets of binder ink 220 arerepresented by circles that are exaggerated in size relative to thesubstrate. The typical size of the inkjet droplets is on the order ofseveral microns. The droplets 220 of binder ink are applied to thesurface of the substrate 200 via a digital inkjet process to recreate(i.e., print) the digital image (or processed version thereof) receivedas an input at step 102 of example process 100. In other words, adigital inkjet printer prints a digital image on the surface of thesubstrate 200 using binder ink. As a result, the surface of thesubstrate 200 includes regions 222 which are covered in a layer ofbinder ink and unprotected regions 232 which are not covered in a layerof binder ink.

Note that the protected layer covering regions 222 of the substrate 200is depicted as extending into the surface of the substrate 200 (theregions of diagonally hatched lines) as opposed to resting on top of thesurface of the substrate 200. This may be due to absorption of thebinder ink by the porous material of the substrate 200. In otherembodiments involving non-porous or less-porous material, the binder inkmay instead rest on top of the surface of the substrate. In any case,the depth to which the binder ink is absorbed into the surface of thesubstrate will depend on a number of factors including the force of theinkjet process, the amount of ink applied, and the porosity of thesubstrate surface. Further, the depth to which the binder ink isabsorbed may be exaggerated in FIGS. 2B and 2C for illustrative clarityand is not necessarily indicative of actual absorption.

Although not depicted in FIG. 1 , in some embodiments example process100 may include waiting for the binder ink to dry or actively applyinganother process, such as a curing process to finalize formation of theprotective layer over certain regions of the surface of the substrate.For example, in some embodiments the binder ink may include or becombined with a curable agent which requires a curing process (e.g.,application of heat, UV light, etc.) to form the protective layer.

Once a protective layer is formed by application of the binder ink,example process 100 proceeds to step 106 which includes removingunprotected regions of the surface of the substrate to form the reliefpattern in the substrate. For example, FIG. 2C shows the removal ofmaterial from the substrate 200 in the unprotected region 232 betweenthe protected regions 222.

In some embodiments, step 106 is performed by brushing away materialfrom the unprotected region 232 of the surface of the substrate.Brushing may be applied manually or preferably automatically using anytype of brushing device. Brushes may comprise fibers (e.g., cotton,polyester, polyamide, polyethylene, polyacrylonitrile, polypropylene,wool, or animal hair) that are affixed to rotatable drums or circularpads. The physical properties of the brushes used in the brushingprocess will depend on several factors such as the type of substrate,the manufacturing process, or decorative requirements. For example, alooser substrate powder, slower production speed, and simple design mayrequire a less aggressive brushing process to achieve a desireddecorative effect. In some embodiments, a brushing process is applied tothe entire surface of the substrate, but the total brushing area mayalso be limited depending on the desired decorative effect.

In some embodiments, the removal of material from the substrate at step106 may be performed using non-contact processes such as compressed air(i.e., air-knife) or powder vacuum. In some embodiments, suchnon-contact processes may be combined with a mechanical brushing toremove material from the surface of the substrate.

As shown in FIG. 2C, removal of material from the unprotected region 232of the substrate 200 results in the formation of a 3D relief of depth Arelative to the original surface of the substrate 200. In the exampledepicted in FIG. 2C, the depth A of the 3D relief is equal to thethickness of the top layer 200 a of the substrate; however, this may notbe the case in all embodiments. For example, in some embodiments, thematerial of the top layer 200 a may exhibit different properties thanthe material of the bottom layer 200 b and the removal process (e.g.,brushing) may be specifically calibrated to only remove the material ofthe top layer 220 a. Alternatively, or in addition, the removal processmay be calibrated (e.g., based on user input received at step 102) toremove material up to a specified depth A that may differ from thethickness of the top layer 200 a. As further depicted in FIG. 2C, the 3Drelief formed by the removal process is defined by vertical side wallsat right angles to the original horizontal surface of the substrate 200.In other words, the 3D relief depicted in FIG. 2C does not exhibit agradient. As will be described later, in some embodiments, the processfor forming the 3D relief can be altered slightly to impart such agradient.

The example process 100 described with respect to FIGS. 2A-2C shows theprotective layer of binder ink remaining in place after the 3D relief isformed. The binder ink may remain in the substrate until it eitherevaporates way or is burned away, for example, during a kiln firingprocess.

Alternatively, in some embodiments this protective layer of binder inkmay be removed from the surface of the substrate after the 3D relief isformed, for example, by applying a solvent. The binder ink may beactively removed through application of a solvent if, for example, thepresence of such binder ink on the surface of the substrate wouldinterfere with other processes such as glazing or color decoration. Insome embodiments, the solvent used to remove the layer of binder ink maybe the same solvent or similar solvent used to form the gradient relief.

As previously mentioned, in some embodiments one or more post-processesmay be applied after forming the 3D relief according to the introducedtechnique. It shall be understood that such post-processes are optionaland are not required to actually form the relief. FIG. 3 is a flowchartillustrating an example process 300 that can be applied to the substrateafter process 100 has been performed. Certain steps of the exampleprocess 300 are described with reference to FIGS. 4A-4C which show asequence of illustrative diagrams depicting the processing of thesubstrate according to process 300. Certain steps of the example process300 depicted in FIG. 3 may be performed by one or more components of theautomated production system 800 depicted in FIG. 8 and/or the examplecomputing system 900 depicted in FIG. 9 . The process 300 described withrespect to FIG. 3 is an example provided for illustrative purposes andis not to be construed as limiting. Other processes may include more orfewer steps than depicted while remaining within the scope of thepresent disclosure. Further, the steps depicted in example process 300may be performed in a different order than is shown.

As mentioned, and as depicted in the flow chart in FIG. 3 , process 300picks up after process 100 is completed. In an example embodiment,process 300 begins at step 302 by applying a layer of glaze to thesurface of the substrate 200. As shown in FIG. 4A, in some embodiments,the glaze may be applied by propelling droplets 440 of glaze at thesurface of the substrate 200 to produce a layer 442 of glaze that coversthe surface of the substrate 200 including the 3D relief. Droplets ofglaze may be propelled using any suitable process such as an inkjetprinter (e.g., similar to the application of the binder ink) or anyother spraying process (automated or manual). The glaze may also beapplied using any other suitable process such brush application(automated or manual) or dipping (automated or manual).

In some embodiments, colored ink may be applied at step 304 afterforming the 3D relief in process 100 and/or after applying the glaze atstep 302. Color may be applied for decorative purposes or for any otherpurpose. As shown in FIG. 4B, in some embodiments, the colored ink maybe applied, for example, by propelling droplets 450 of one or morecolors of ink at the surface of the substrate 200 to produce a layer ofcolor 452 on the surface of the substrate or glaze (if applied). Thedroplets 450 of colored ink may be propelled using any suitable processsuch as an inkjet printer (e.g., similar to the application of thebinder ink) or any other spraying process (automated or manual). Thecolored ink may also be applied using any known analog technique such aspaintbrush, gravure, screen printing, etc.

In some embodiments, colored ink is applied using inkjet printing basedon the same digital image used to print the binder ink in process 100.Using digital inkjet printing to both form the 3D relief and applydecorative color allows the formed relief to match (i.e., align with)the digitally printed color designs. This contrasts with the inherentdifficulty in aligning a digitally printed image with a relief formedusing an analog process such as stamping. In some embodiments, thecolors to be applied during step 304 are defined by data in the digitalimage itself and/or by additional input received, for example from auser, at step 102.

Depending on the type of substrate used, example process 300 mayconclude with, at step 306, firing (i.e., applying heat to) thesubstrate to produce the final product 490, for example, as depicted atFIG. 4C. Note that the previously defined layers 200 a and 200 b ofsubstrate 200 have combined through the firing process to produce afinal tile product 490. This firing process may similarly be appliedwithout the application of a glaze or decorative color ink. Aspreviously mentioned, a typical industrial ceramic tile process involvesfiring for approximately 1-2 hours at a temperature between 1030° C. and1250° C.; however, the specifics of the firing process, if applied, willdepend on the material of the substrate.

The introduced technique can further be used to apply gradient 3D reliefto a substrate. FIG. 5 shows a flowchart illustrating a second exampleprocess 500 for applying gradient 3D relief to a substrate using digitalinkjet technology. Certain steps of the example process 500 aredescribed with reference to FIGS. 6A-6D which show a sequence ofillustrative diagrams depicting processing of a substrate according tothe introduced technique. Certain steps of the example process 500depicted in FIG. 5 may be performed by one or more components of theautomated production system 800 depicted in FIG. 8 and/or the examplecomputing system 900 depicted in FIG. 9 . The process 500 described withrespect to FIG. 5 is an example provided for illustrative purposes andis not to be construed as limiting. Other processes may include more orfewer steps than depicted while remaining within the scope of thepresent disclosure. Further, the steps depicted in example process 500may be performed in a different order than is shown.

Example process 500 begins at step 502 with receipt of an input definingthe relief pattern that will be applied to a substrate such as a ceramictile. The input received at step 502 may be the same or contain similardata as the input received at step 102 in example process 100 describedwith respect to FIG. 1 . In some embodiments, in addition to definingthe relief pattern, the input received at step 502 may define thegradient to be applied in the relief pattern. The gradient may bedefined for example, as a separate parameter, for example, input by auser. Alternatively, the gradient may be defined by the digital imageincluded within the input. For example, the digital image may includegradient values (e.g., between black and white) that, when processed bya computer processing system, can be interpreted as a gradient propertyof the 3D relief to be formed in the substrate.

Example process 500 continues at step 504 with applying binder ink toform a protective barrier layer over a portion of the surface of thesubstrate based upon the input received at step 502. Step 504 ofapplication of binder ink to the surface of a substrate may be the sameor similar to step 104 in example process 100 described with respect toFIG. 1 . For example, similar to FIG. 2A, FIG. 6A shows a profile viewof a substrate 600 which includes a top layer 600 a (e.g., a doublecharge layer) and a bottom layer 600 b. FIG. 6B shows a profile view ofthe same substrate 600 with binder ink applied to form a protectivelayer over a region of the surface of the substrate 600. As with step104 in process 100, step 504 may include application of the binder inkusing an inkjet process by propelling droplets 620 of the binder inkinto the surface of the substrate 600. As a result, the surface of thesubstrate 600 includes regions 622 b that are covered in a layer ofbinder ink and unprotected regions 632 b that are not covered in a layerof binder ink.

Example process 500 continues at step 506 with the application ofsolvent ink over the applied binder ink to force at least some of theapplied binder ink into the substrate. For example, as depicted in FIG.6C, the solvent ink can be applied using an inkjet process by propellingdroplets 624 of solvent ink into the surface of the substrate.Application of the droplets 624 of solvent ink forces at least some ofthe previously applied binder ink to sink into the substrate 600.

The depth to which the binder ink sinks into the substrate 600 maydepend upon the amount of solvent ink applied at any given area. Varyingthe amount of solvent ink applied across the surface of the substrate600 (e.g., as indicated by the varying number of droplets 624) cantherefore produce a gradient in the protective layer formed by thebinder ink within the substrate 600. This is represented in FIG. 6C bythe protected regions 622 c that are now within the top layer 600 a ofthe substrate 600 and are at an angle relative to the horizontal surfaceof the substrate.

The depth to which the binder ink sinks within the substrate will alsodepend upon the material properties of the substrate. In the exampledepicted in FIG. 6C, the protective layer 622 of binder ink has onlysunk as far as the depth of the top layer 600 a (e.g., the double chargelayer) of the substrate 600. This may be due, for example, to a higherporosity of the top layer 600 a relative to the bottom layer 600 b. Aspreviously discussed, the introduced technique can similarly be appliedin substrates having more or fewer than two layers. Accordingly, inother embodiments, the addition of solvent ink may affect the layer ofbinder ink differently than as depicted in FIG. 6C.

Although not depicted in FIG. 5 , in some embodiments, example process500 may include waiting for the binder ink to dry or actively applyinganother process to finalize formation of the protective layer 622 cwithin the substrate 600. For example, in some embodiments, the binderink may include or be combined with a curable agent that requires acuring process (e.g., application of heat, UV light, etc.) to form theprotective layer 622 c. As another example, a washing process may beapplied to remove excess solvent ink from the substrate 600.

Once a protective layer is formed by application of the binder ink andsolvent ink, example process 500 proceeds to step 508 which includesremoving material from unprotected regions (e.g., unprotected region 632c) of the surface of the substrate to form the relief pattern in thesubstrate. For example, FIG. 6D shows the removal of material from thesubstrate 600 in the unprotected region 632 c between the protectedregions 622 c.

As shown in FIG. 6C, removal of material from the unprotected region 632c of the substrate 600 results in the formation of a 3D relief of depthB relative to the original surface of the substrate 600. In the exampledepicted in FIG. 6D, the depth B of the 3D relief is equal to thethickness of the top layer 600 a of the substrate; however, this may notbe the case in all embodiments. For example, in some embodiments, thematerial of the top layer 600 a may exhibit different properties thanthe material of the bottom layer 600 b and the removal process (e.g.,brushing) may be specifically calibrated to only remove the material ofthe top layer 620 a. Alternatively, or in addition, the removal processmay be calibrated (e.g., based on user input received at step 502) toremove material up to a specified depth B that may differ from thethickness of the top layer 600 a. As further depicted in FIG. 6D, the 3Drelief formed by the removal process is defined by sloped side walls. Inother words, the resulting relief has a gradient. More specifically, thegradient of the resulting relief can be defined based on the ratiobetween the elevation change of the sloped side walls (i.e., gradientdepth B) and the horizontal length C of the sloped side walls. Note thatthe resulting side walls in the example depicted in FIG. 6D have aconstant slope. The introduced technique can similarly be applied toform side walls with varying slope, for example, by adjusting how thesolvent ink is applied at step 506.

As previously mentioned, in some embodiments one or more post-processesmay be applied after forming the 3D relief according to the introducedtechnique. Again, FIG. 3 shows a flowchart illustrating an exampleprocess 300 that can be applied to a substrate after forming the relief.FIGS. 7A-7C show a sequence of illustrative diagrams depicting theprocessing of the substrate 600 according to the previously describedprocess 300. Specifically, FIG. 7A shows the application of droplets 740of glaze to the surface of substrate 600 to form a layer 742 of glaze.FIG. 7B shows the application of droplets 750 of colored ink to producea layer of color 752 on the surface of the substrate 600 or glaze (ifapplied). FIG. 7C shows a final product 790 which results from firingthe substrate 600.

Example Implementation of Applying 3D Relief to a Substrate UsingDigital Inkjet Technology

FIG. 8 is a diagram of an example automated production system 800 thatcan be configured to implement the introduced technique for applying 3Drelief to a substrate using digital inkjet technology. The automatedproduction system 800 may be configured, for example, to mass produceceramic tiles with 3D relief using the introduced technique.

The automated production system 800 may include a master controller 802for the automated production system 800 controls one or more controllersfor related subsystems based on received inputs 804. The mastercontroller may include any combination of hardware and/or softwareconfigured to receive the inputs 804, process the inputs 804, andgenerate outputs, for example, in the form of control commands to one ormore subsystems based on the processing.

The inputs 804 received by the master controller may include, forexample, digital image data and/or any other input as described withrespect to steps 102 and 502 of example processes 100 and 500(respectively).

The automated production system 800 may further include an inkjetprinting system configured to apply various types of ink to the surfaceof a substrate 850. The inkjet printing system may include a printsystem controller 806 comprising any combination of hardware and/orsoftware configured to receive control commands from the mastercontroller 802, interpret the commands, and generate control commandsconfigured to cause one or more inkjet printers 807 to propel dropletsof various types of ink onto the surface of the substrate. The varioustypes of ink may include, for example, binder ink, solvent ink, andcolor ink. In some embodiments, the inkjet printing system includesmultiple inkjet printers each configured to apply to a different type ofink.

The automated production system 800 may further include a brushingsystem configured to remove material from the surface of a substrate 850to form 3D relief patterns. The brushing system may include a brushingsystem controller 808 comprising any combination of hardware and/orsoftware configured to receive control commands from the mastercontroller 802, interpret the commands, and generate control commandsconfigured to cause one or more automated brushers 809 to brush thesurface of the substrate 850 to remove material from the surface of thesubstrate. Although not depicted in FIG. 8 , other types of mechanicaland/or chemical systems for removal of material from the surface of thesubstrate 850 may similarly be integrated into an automated productionsystem.

The automated production system 800 may further include a glazing systemconfigured to apply a glaze to the surface of the substrate 850 afterthe 3D relief has been formed using the inkjet printing system and thebrushing system. The glazing system may include a glaze controller 810comprising any combination of hardware and/or software configured toreceive control commands from the master controller 802, interpret thecommands, and generate control commands configured to cause one or moreglaze applicators 811 to apply a glaze to the surface of the substrate850. As previously discussed, in some embodiments, glaze maybe appliedthrough inkjet printing, in which case the glazing system may be part ofthe inkjet printing system. Alternatively, the glazing system maycomprise a separate automated system as indicated in FIG. 8 .

The automated production system 800 may further include an automatedkiln configured to fire the substrate 850 to produce the final tileproduct. The automated kiln may include a kiln system controller 812comprising any combination of hardware and/or software configured toreceive control commands from the master controller 802, interpret thecommands, and generate control commands configured to cause one or moreheating elements 813 to apply heat to the substrate 850 to produce thefinal tile product.

Various components of the automated production system 800, such as thevarious system controllers 802, 806, 808, 810, and 812 may include oneor more of the components of the example computing system 900 describedwith respect to FIG. 9 . It shall be appreciated that the example system800 described with respect to FIG. 8 is an example and is described insimplified terms for illustrative clarity. A person having ordinaryskill will recognize that, in practice, a similar system may includemore or fewer components than are shown or may order and arrange thecomponents differently, while still remaining within the scope of thedisclosed innovation.

Example Computing System

FIG. 9 is a block diagram of an example computing system 900 as may beused to implement certain features of some of the embodiments. Thecomputing system 900 may be a server computer, a client computer, apersonal computer (PC), a user device, a tablet PC, a laptop computer, apersonal digital assistant (PDA), a cellular telephone, a telephone, aweb appliance, a network router, switch or bridge, a console, ahand-held console, a (hand-held) gaming device, a music player, anyportable, mobile, hand-held device, wearable device, or any othermachine capable of executing a set of instructions (sequential orotherwise) that specify actions to be taken by that machine.

The computing system 900 may include one or more processing units (e.g.,central processing units (CPU) and/or graphical processing units (GPU)(collectively the “processor”) 905, one or more memory units(collectively “memory”) 910, one or more input/output devices 925 (e.g.keyboard and pointing devices, touch devices, display devices, audioinput/output devices, etc.) one or more storage devices 920 (e.g. diskdrives, solid state drives, etc.), and one or more network adapters 930(e.g., network interfaces) that can communicatively couple via aninterconnect 915. The interconnect 915 is illustrated as an abstractionthat represents any one or more separate physical buses, point to pointconnections, or both connected by appropriate bridges, adapters, orcontrollers. The interconnect 915, therefore, may include, for example,a system bus, a Peripheral Component Interconnect (PCI) bus orPCI-Express bus, a HyperTransport or industry standard architecture(ISA) bus, a small computer system interface (SCSI) bus, a universalserial bus (USB), IIC (12C) bus, an Institute of Electrical andElectronics Engineers (IEEE) standard 1394 bus (also called Firewire),or any other suitable system for facilitating communication between thevarious components of the example computing system 900.

The memory 910 and storage device 920 are computer-readable storagemedia that may store instructions that implement at least portions ofthe various embodiments. In addition, the data structures and messagestructures may be stored or transmitted via a data transmission medium(e.g., a signal on a communications link). Various communication linksmay be used such as the Internet, a local area network, a wide areanetwork, or a point-to-point dial-up connection, etc. Thus, computerreadable media can include computer-readable storage media, e.g.non-transitory media, and computer-readable transmission media.

The instructions stored in memory 910 can be implemented as softwareand/or firmware to program the processor 905 to carry out actionsdescribed above. In some embodiments such software or firmware may beinitially provided to the processer 905 by downloading the software orfirmware from a remote system through the computing system 1500, e.g.,via network adapter 930.

FIG. 10 is a block diagram that illustrates an example machine learning(ML) system 1000 that can implement aspects of the present technology.The ML system 1000 is implemented using components of the examplecomputer system 1100 illustrated and described in more detail withreference to FIG. 11 . For example, the ML system 1000 can beimplemented on the processor 1102 using instructions 1108 programmed inthe memory 1106 illustrated and described in more detail with referenceto FIG. 11 . Likewise, implementations of the ML system 1000 can includedifferent and/or additional components or be connected in differentways. The ML system 1000 is sometimes referred to as a ML module.

The ML system 1000 includes a feature extraction module 1008 implementedusing components of the example computer system 1100 illustrated anddescribed in more detail with reference to FIG. 11 . In someimplementations, the feature extraction module 1008 extracts a featurevector 1012 from input data 1004. For example, the input data 1004 canbe information defining a relief pattern for forming a three-dimensional(3D) relief using an inkjet printer. Examples of such information aredescribed in more detail with reference to FIGS. 1-8 . The featurevector 1012 includes features 1012 a, 1012 b, . . . , 1012 n. Forexample, the feature extraction module 1008 extracts a feature vectorfrom a digital image of a design upon which the relief pattern will bebased as described in more detail with reference to FIGS. 1-8 .

The feature extraction module 1008 reduces the redundancy in the inputdata 1004, e.g., repetitive data values, to transform the input data1004 into the reduced set of features 1012, e.g., features 1012 a, 1012b, . . . , 1012 n. The feature vector 1012 contains the relevantinformation from the input data 1004, such that events or data valuethresholds of interest can be identified by the ML model 1016 by usingthis reduced representation. In some example implementations, thefollowing dimensionality reduction techniques are used by the featureextraction module 1008: independent component analysis, Isomap, kernelprincipal component analysis (PCA), latent semantic analysis, partialleast squares, PCA, multifactor dimensionality reduction, nonlineardimensionality reduction, multilinear PCA, multilinear subspacelearning, semidefinite embedding, autoencoder, and deep featuresynthesis.

In alternate implementations, the ML model 1016 performs deep learning(also known as deep structured learning or hierarchical learning)directly on the input data 1004 to learn data representations, asopposed to using task-specific algorithms. In deep learning, no explicitfeature extraction is performed; the features 1012 are implicitlyextracted by the ML system 1000. For example, the ML model 1016 can usea cascade of multiple layers of nonlinear processing units for implicitfeature extraction and transformation. Each successive layer uses theoutput from the previous layer as input. The ML model 1016 can thuslearn in supervised (e.g., classification) and/or unsupervised (e.g.,pattern analysis) modes. The ML model 1016 can learn multiple levels ofrepresentations that correspond to different levels of abstraction,wherein the different levels form a hierarchy of concepts. In thismanner, the ML model 1016 can be configured to differentiate features ofinterest from background features.

In alternative example implementations, the ML model 1016, e.g., in theform of a CNN generates the output 1024, without the need for featureextraction, directly from the input data 1004. For example, the output1024 includes control commands to an inkjet printer and a mechanicalbrusher to form a 3D relief on a substrate based on a relief pattern.The output 1024 is provided to the computer device 1028 or the computersystem described in more detail with reference to FIGS. 3-8 . Thecomputer device 1028 is a server, computer, tablet, smartphone, smartspeaker, etc., implemented using components of the example computersystem 1100 illustrated and described in more detail with reference toFIG. 11 . In some implementations, the steps performed by the ML system1000 are stored in memory on the computer device 1028 for execution. Inother implementations, the output 1024 is displayed on the displaydevice 1118 illustrated and described in more detail with reference toFIG. 11 .

The ML model 1016 can be a CNN that includes both convolutional layersand max pooling layers. A CNN is a type of feed-forward artificialneural network in which the connectivity pattern between its neurons isinspired by the organization of a visual cortex. Individual corticalneurons respond to stimuli in a restricted area of space known as thereceptive field. The receptive fields of different neurons partiallyoverlap such that they tile the visual field. The response of anindividual neuron to stimuli within its receptive field can beapproximated mathematically by a convolution operation. CNNs are basedon biological processes and are variations of multilayer perceptronsdesigned to use minimal amounts of preprocessing. The architecture ofthe ML model 1016 can be “fully convolutional,” which means thatvariable-sized test location data vectors can be fed into it. For allconvolutional layers, the ML model 1016 can specify a kernel size, astride of the convolution, and an amount of zero padding applied to theinput of that layer. For the pooling layers, the model 1016 can specifythe kernel size and stride of the pooling.

In some implementations, the ML system 1000 trains the ML model 1016,based on the training data 1020, to correlate the feature vector 1012 toexpected outputs in the training data 1020. For example, the ML model1016 is trained to configure an inkjet printer to apply binder ink to afirst region of a surface of a substrate, and configure a mechanicalbrusher to brush the surface of the substrate to remove material from asecond region of the surface of the substrate, as described in moredetail with reference to FIG. 12 . As part of the training of the MLmodel 1016, the ML system 1000 forms a training set of features andtraining labels by identifying a positive training set of features thathave been determined to have a desired property in question, and, insome implementations, forms a negative training set of features thatlack the property in question.

The ML system 1000 applies ML techniques to train the ML model 1016,that when applied to the feature vector 1012, outputs indications ofwhether the feature vector 1012 has an associated desired property orproperties, such as a probability that the feature vector 1012 has aparticular Boolean property, or an estimated value of a scalar property.The ML system 1000 can further apply dimensionality reduction (e.g., vialinear discriminant analysis (LDA), PCA, or the like) to reduce theamount of data in the feature vector 1012 to a smaller, morerepresentative set of data.

The ML system 1000 can use supervised ML to train the ML model 1016,with feature vectors of the positive training set and the negativetraining set serving as the inputs. In some implementations, differentML techniques, such as linear support vector machine (linear SVM),boosting for other algorithms (e.g., AdaBoost), logistic regression,naïve Bayes, memory-based learning, random forests, bagged trees,decision trees, boosted trees, boosted stumps, neural networks, CNNs,etc., are used. In some example implementations, a validation set 1032is formed of additional features, other than those in the training data1020, which have already been determined to have or to lack the propertyin question. The ML system 1000 applies the trained ML model 1016 to thefeatures of the validation set 1032 to quantify the accuracy of the MLmodel 1016. Common metrics applied in accuracy measurement include:Precision and Recall, where Precision refers to a number of results theML model 1016 correctly predicted out of the total it predicted, andRecall is a number of results the ML model 1016 correctly predicted outof the total number of features that had the desired property inquestion. In some implementations, the ML system 1000 iterativelyre-trains the ML model 1016 until the occurrence of a stoppingcondition, such as the accuracy measurement indication that the ML model1016 is sufficiently accurate, or a number of training rounds havingtaken place.

The validation set 1032 can include monochrome images of designsdefining areas corresponding to relief patterns to be printed,polychrome images which define both relief patterns to be applied aswell as coloring, parameters including types of substrates (e.g.,material type, dimensions, etc.), dimensions of reliefs (e.g., depths,gradients, etc.), data describing post-processes (e.g., glazing, colorprinting, firing, etc.), or any other relevant parameters. Training dataor the information received by a computer system operating the inkjetprinter can also include processing data (e.g., data included in thereceived inputs) by a computer processing system. As an illustrativeexample, a digital image including a design in black against a whitebackground defining a relief pattern may be processed to invert colorvalues such that the printed portions (i.e., the black portions of theimage) define areas of the substrate which will be protected fromremoval, for example, by brushing. This allows the detected values to bevalidated using the validation set 1032. The validation set 1032 can begenerated based on analysis to be performed.

In some embodiments, ML system 1000 is a generative artificialintelligence or generative AI system capable of generating text, images,or other media in response to prompts. Generative AI systems usegenerative models such as large language models to produce data based onthe training data set that was used to create them. A generative AIsystem is constructed by applying unsupervised or self-supervisedmachine learning to a data set. The capabilities of a generative AIsystem depend on the modality or type of the data set used. For example,generative AI systems trained on words or word tokens are capable ofnatural language processing, machine translation, and natural languagegeneration and can be used as foundation models for other tasks. Inaddition to natural language text, large language models can be trainedon programming language text, allowing them to generate source code fornew computer programs. Generative AI systems trained on sets of imageswith text captions are used for text-to-image generation and neuralstyle transfer.

Computer System

FIG. 11 is a block diagram that illustrates an example of a computersystem in which at least some operations described herein can beimplemented. As shown, the computer system 1100 can include: one or moreprocessors 1102, main memory 1106, non-volatile memory 1110, a networkinterface device 1112, video display device 1118, an input/output device1120, a control device 1122 (e.g., keyboard and pointing device), adrive unit 1124 that includes a storage medium 1126, and a signalgeneration device 1130 that are communicatively connected to a bus 1116.The bus 1116 represents one or more physical buses and/or point-to-pointconnections that are connected by appropriate bridges, adapters, orcontrollers. Various common components (e.g., cache memory) are omittedfrom FIG. 11 for brevity. Instead, the computer system 1100 is intendedto illustrate a hardware device on which components illustrated ordescribed relative to the examples of the figures and any othercomponents described in this specification can be implemented.

The computer system 1100 can take any suitable physical form. Forexample, the computing system 1100 can share a similar architecture asthat of a server computer, personal computer (PC), tablet computer,mobile telephone, game console, music player, wearable electronicdevice, network-connected (“smart”) device (e.g., a television or homeassistant device), AR/VR systems (e.g., head-mounted display), or anyelectronic device capable of executing a set of instructions thatspecify action(s) to be taken by the computing system 1100. In someimplementation, the computer system 1100 can be an embedded computersystem, a system-on-chip (SOC), a single-board computer system (SBC) ora distributed system such as a mesh of computer systems or include oneor more cloud components in one or more networks. Where appropriate, oneor more computer systems 1100 can perform operations in real-time, nearreal-time, or in batch mode.

The network interface device 1112 enables the computing system 1100 tomediate data in a network 1111 with an entity that is external to thecomputing system 1100 through any communication protocol supported bythe computing system 1100 and the external entity. Examples of thenetwork interface device 1112 include a network adaptor card, a wirelessnetwork interface card, a router, an access point, a wireless router, aswitch, a multilayer switch, a protocol converter, a gateway, a bridge,bridge router, a hub, a digital media receiver, and/or a repeater, aswell as all wireless elements noted herein.

The memory (e.g., main memory 1106, non-volatile memory 1110,machine-readable medium 1126) can be local, remote, or distributed.Although shown as a single medium, the machine-readable medium 1126 caninclude multiple media (e.g., a centralized/distributed database and/orassociated caches and servers) that store one or more sets ofinstructions 1128. The machine-readable (storage) medium 1126 caninclude any medium that is capable of storing, encoding, or carrying aset of instructions for execution by the computing system 1100. Themachine-readable medium 1126 can be non-transitory or comprise anon-transitory device. In this context, a non-transitory storage mediumcan include a device that is tangible, meaning that the device has aconcrete physical form, although the device can change its physicalstate. Thus, for example, non-transitory refers to a device remainingtangible despite this change in state.

Although implementations have been described in the context of fullyfunctioning computing devices, the various examples are capable of beingdistributed as a program product in a variety of forms. Examples ofmachine-readable storage media, machine-readable media, orcomputer-readable media include recordable-type media such as volatileand non-volatile memory devices 1110, removable flash memory, hard diskdrives, optical disks, and transmission-type media such as digital andanalog communication links.

In general, the routines executed to implement examples herein can beimplemented as part of an operating system or a specific application,component, program, object, module, or sequence of instructions(collectively referred to as “computer programs”). The computer programstypically comprise one or more instructions (e.g., instructions 1104,1108, 1128) set at various times in various memory and storage devicesin computing device(s). When read and executed by the processor 1102,the instruction(s) cause the computing system 1100 to perform operationsto execute elements involving the various aspects of the disclosure.

FIG. 12 is a flowchart that illustrates an example process forgenerating three-dimensional (3D) reliefs on tiles using inkjetprinting. In some implementations, the process is performed by theprinting system 1300 described in more detail with reference to FIG. 13. In some implementations, the process is performed by a computersystem, e.g., the example computer system 1100 illustrated and describedin more detail with reference to FIG. 11 . Particular entities, forexample, the controllers and mechanisms illustrated and described inmore detail with reference to FIG. 8 perform some or all of the steps ofthe process in other implementations. Likewise, implementations caninclude different and/or additional steps or can perform the steps indifferent orders.

In step 1204, a computer system receives information defining a reliefpattern for forming a 3D relief on a substrate using a digital inkjetprinter. Examples of the information received (e.g., a digital imagefile) are described in more detail with reference to FIGS. 1-8 . In someembodiments, the information is a polychrome image. Example reliefpatterns and example 3D reliefs are described in more detail withreference to FIGS. 1-8 . Example digital inkjet printers are describedin more detail with reference to FIGS. 1-8 and 13-14 . In someembodiments, the substrate is a double-charged ceramic tile including atop layer of absorbent material upon which ink can be applied usingdigital inkjet printing. In some embodiments, the substrate includes atleast one of polyvinyl chloride (PVC), polymethyl methacrylate (PMMA),acrylonitrile butadiene styrene (ABS), or luxury vinyl tile (LVT).Example of substrate materials are described in more detail withreference to FIGS. 1-8 .

In step 1208, the computer system extracts, from the information, afeature vector including one or more features describing the 3D relief.Example feature vectors are illustrated and described in more detailwith reference to FIG. 10 .

In step 1212, the computer system generates, using a machine learningmodel, control commands based on the feature vector. Example machinelearning models are illustrated and described in more detail withreference to FIG. 10 . Example control commands are described in moredetail with reference to FIG. 8 . In some embodiments, the machinelearning model is trained, based on parameters associated with forming3D reliefs in substrates.

In some embodiments, the parameters include a material type of thesubstrate or dimensions of the substrate. Example material types ofsubstrates and dimensions are described in more detail with reference toFIGS. 1-8 . In some embodiments, the parameters include a depth of the3D relief or a gradient of the 3D relief. Example depths and gradient of3D reliefs are described in more detail with reference to FIGS. 1-8 . Insome embodiments, the parameters describe at least one of a glazingprocess, a color printing process, or a firing process. Examples of aglazing process, a color printing process, and a firing process aredescribed in more detail with reference to FIGS. 1-8 .

The machine learning model is trained to generate the control commandsto configure the digital inkjet printer to apply binder ink to a firstregion of a surface of the substrate. Application of binder ink to aregion of a surface of a substrate is described in more detail withreference to FIGS. 1-8 . The applied binder ink is configured to form aprotective layer over the first region of the surface of the substrate.Formation of a protective layer over a region of a surface of asubstrate using binder ink is described in more detail with reference toFIGS. 1-8 . In some embodiments, the binder ink includes a resinsolution.

In some embodiments, the machine learning model is trained to generatethe control commands to configure the digital inkjet printer to applysolvent ink to the surface of the substrate after applying the binderink to the first region of the surface of the substrate. Application ofsolvent ink is described in more detail with reference to FIGS. 1-8 .Applying the solvent ink causes at least some of the binder ink to sinkinto the surface of the substrate such that the protective layer formedby the binder ink is at a gradient depth relative to the surface of thesubstrate. The solvent ink is applied before brushing the surface of thesubstrate.

In some embodiments, the machine learning model is trained to generatethe control commands to configure a mechanical brusher to brush thesurface of the substrate to remove material from an unprotected secondregion of the surface of the substrate. Brushing a surface of asubstrate to remove material is described in more detail with referenceto FIGS. 1-8 . Removing the material from the unprotected second regionof the surface of the substrate forms a gradient 3D relief. Examplegradient 3D reliefs are described in more detail with reference to FIGS.1-8 .

In some embodiments, the machine learning model is trained to generatethe control commands to configure the digital inkjet printer to applycolor ink to the surface of the substrate after the 3D relief has beenformed. Application of color ink to the surface of the substrate afterthe 3D relief has been formed is described in more detail with referenceto FIGS. 1-8 . In some embodiments, the machine learning model istrained to generate the control commands to configure a glazingapparatus to apply glaze to the surface of the substrate after the 3Drelief has been formed. Application of glaze to a surface of a substrateafter a 3D relief has been formed is described in more detail withreference to FIGS. 1-8 .

In step 1216, the computer system transmits the control commands to thedigital inkjet printer to form the 3D relief on the substrate based onthe relief pattern. In some embodiments, the machine learning model istrained to generate the control commands to configure an automated kilnto fire the substrate after the 3D relief has been formed to produce aceramic tile. Firing a substrate after a 3D relief has been formed isdescribed in more detail with reference to FIGS. 1-8 .

FIG. 13 is a block diagram illustrating a perspective view of a printingsystem 1300, in accordance with one or more embodiments. The printingsystem 1300 includes a printer head 1306, at least one light source1312, and a transfer belt 1302. Embodiments may include variouscombinations of these and other components, e.g., a dryer. For example,the light source 1312 may be present in some embodiments, but not inothers. As another example, a dryer may be included if the image 1310will not be quickly transferred to a substrate. While the printingsystem 1300 of FIG. 13 includes a transfer belt 1302, other means forconveying and/or retaining transfer material 1304 can also be used, suchas a rotating platform or stationary bed.

The printer head 1306 is configured to deposit ink onto a transfermaterial 1304 in the form of an image 1310. The transfer material 1304,which may also be referred to as a former material, is flexible, whichallows the image 1310 to be transferred to complex-shaped substrates.For example, the transfer material 1304 may be a rubber former, athermoformable material, etc. In some embodiments, the printer head 1306is an inkjet printer head that jets ink onto the transfer material 1304using, for example, piezoelectric nozzles. Thermal printer heads aregenerally avoided in an effort to avoid premature sublimation of theink. In some embodiments, the ink is a solid energy, e.g., UV, curableink. However, other inks may also be used, such as water-based energycurable inks or solvent-based energy curable inks. The ink can bedeposited in different forms, such as ink droplets and colored polyesterribbons.

In some embodiments, one or more light sources 1312 cure some or all ofthe ink deposited onto the transfer material 1304 by emitting UVradiation. The light source(s) 1312 may be, for example, a UVfluorescent bulb, a UV light emitting diode (LED), a low-pressure, e.g.,mercury (Hg), bulb, or an excited dimer (excimer) lamp and/or laser.Various combinations of these light sources could be used. For example,a printing system 1300 may include a low-pressure Hg lamp and a UV LED.As discussed in more detail with reference to FIG. 2 , the light source1312 may be configured to emit UV radiation of a particular subtype.

The printer head 1306 and light source 1312 are illustrated as beingdirectly adjacent to one another, i.e., neighboring without anyintervening components. However, additional components that assist inprinting, curing, etc., may also be present. For example, multipledistinct light sources 1312 may be positioned behind the printer head1306. FIG. 13 illustrates one possible order in which components may bearranged in order to print an image 1310 onto the former transfermaterial 1304. Other embodiments are considered in which additionalcomponents are placed before, between, or after the illustratedcomponents, etc.

In some embodiments, one or more of the aforementioned components arehoused within one or more carriages. For example, the printer head 1306can be housed within a printing carriage 1308, the light source 1312 canbe housed within a curing carriage 1314, etc., In addition to protectingthe components from damage, the carriages may also serve other benefits.For example, the curing carriage 1314 can limit what portion(s) of thetransfer material 1304 and image 1310 are exposed during the curingprocess. The printing system 1300 may include pulleys, motors, rails,and/or any combination of mechanical or electrical technologies thatenable the carriages to travel along the transfer belt 1302, i.e., withrespect to the transfer material 1304. In alternative embodiments, thecarriages can be fixedly attached to a rail or base of the printingsystem 1300. In these embodiments, the transfer material 1304 can bemoved in relation to the printer head 1306, light source 1312, etc.,such that ink can be deposited onto the transfer material 1304.

In various embodiments, some or all of the components are controlled bya computer system 1316. The computer system 1316 is the same as orsimilar to the computer system 500 illustrated and described in moredetail with reference to FIG. 7 . The computer system 1316 can allow auser to input printing instructions and information, modify printsettings, e.g., by changing cure settings, alter the printing process,etc.

FIG. 14 is a block diagram illustrating a side view of a printing system1400, including a printer head 1402 and a light source 1404, inaccordance with one or more embodiments. While a single-passconfiguration is illustrated by FIG. 14 , other embodiments may employmulti-pass, i.e., scan, configurations. Similarly, embodiments can bemodified for various printers, e.g., flatbed printer, drum printer, orlane printer. For example, a flatbed printer may include a stable bedand a traversing printer head, a stable printer head and a traversingbed, etc.

The printer head 1402 can include distinct ink/color drums, e.g., cyan,magenta, yellow, and key (CMYK), or colored polyester ribbons that aredeposited onto the surface of a transfer material 1406. Path Arepresents the media feed direction, e.g., the direction in which thetransfer material 1406 travels during the printing process. Path Drepresents the distance between the printer head 1402 and the surface ofthe transfer material 1406.

As described above, both direct and indirect printing haveconventionally been carried out only on flat surfaces. The printingsystems and methods described herein, however, allow images to beprinted on complex-shaped, i.e., non-planar, surfaces by depositing inkdirectly onto a transfer material 1406 and then transferring the ink toa substrate. When printing directly onto a surface, print quality relieson accuracy of ink drop placement. Therefore, maintaining a constant ornearly constant distance between the printer head 1402 and the flatsurface of the transfer material 1406 is necessary. Airflow, velocityvariability, etc., can affect drop placement even when the change indistance is small, e.g., a few millimeters.

In some embodiments, a light source 1404 cures some or all of the ink1408 deposited onto the transfer material 1406 by the printer head 1402.The light source 1404 may be configured to emit wavelengths of UVelectromagnetic radiation of subtype V (UVV), subtype A (UVA), subtype B(UVB), subtype C (UVC), or any combination thereof. Generally, UVVwavelengths are those wavelengths measured between 395 nanometers (nm)and 445 nm, UVA wavelengths measure between 315 nm and 395 nm, UVBwavelengths measure between 280 nm and 315 nm, and UVC wavelengthsmeasure between 100 nm and 280 nm. However, one skilled in the art willrecognize these ranges are somewhat adjustable. For example, someembodiments may characterize wavelengths of 285 nm as UVC.

The light source 1404 may be, for example, a fluorescent bulb, a lightemitting diode (LED), a low-pressure, e.g., mercury (Hg), bulb, or anexcited dimer (excimer) lamp/laser. Combinations of different lightsources could be used in some embodiments. Generally, the light source1404 is selected to ensure that the curing temperature does not exceedthe temperature at which the ink 1408 begins to sublime. For example,light source 1404 of FIG. 14 is a UV LED lamp that generates low heatoutput and can be used for a wider range of former types. UV LED lampsare associated with lower power consumption, longer lifetimes, and morepredictable power output.

Other curing processes may also be used, such as epoxy (resin)chemistries, flash curing, and electron beam technology. One skilled inthe art will appreciate that many different curing processes could beadopted that utilize specific timeframes, intensities, rates, etc. Theintensity may increase or decrease linearly or non-linearly, e.g.,exponentially, logarithmically. In some embodiments, the intensity maybe altered using a variable resistor or alternatively by applying apulse-width-modulated (PWM) signal to the diodes in the case of an LEDlight source.

The various embodiments introduced herein can be implemented by, forexample, programmable circuitry, e.g., one or more microprocessors,programmed with software and/or firmware, or entirely in special-purposehardwired (non-programmable) circuitry, or in a combination of suchforms. Special-purpose hardwired circuitry may be in the form of, forexample, one or more ASICs, PLDs, FPGAs, etc.

I/We claim:
 1. A machine learning-based method for forming athree-dimensional (3D) relief on a substrate, the method comprising:receiving, by a computer system, information defining a relief patternfor forming the 3D relief using a digital inkjet printer; extracting,from the information, a feature vector comprising one or more featuresdescribing the 3D relief; generating, using a machine learning model,control commands based on the feature vector, wherein the machinelearning model is trained to generate the control commands to: configurethe digital inkjet printer to apply binder ink to a first region of asurface of the substrate, wherein the applied binder ink is configuredto form a protective layer over the first region of the surface of thesubstrate; configure the digital inkjet printer to apply solvent ink tothe surface of the substrate after applying the binder ink to the firstregion of the surface of the substrate; and configure a mechanicalbrusher to brush the surface of the substrate to remove material from anunprotected second region of the surface of the substrate, whereinremoving the material from the unprotected second region of the surfaceof the substrate forms a gradient 3D relief; and transmitting thecontrol commands to the digital inkjet printer to form the 3D relief onthe substrate based on the relief pattern.
 2. The method of claim 1,wherein applying the solvent ink causes at least some of the binder inkto sink into the surface of the substrate such that the protective layerformed by the binder ink is at a gradient depth relative to the surfaceof the substrate.
 3. The method of claim 1, wherein the binder inkincludes a resin solution.
 4. The method of claim 1, wherein thesubstrate is a double-charged ceramic tile including a top layer ofabsorbent material upon which ink can be applied using digital inkjetprinting.
 5. The method of claim 1, wherein the machine learning modelis trained to generate the control commands to: configure a glazingapparatus to apply glaze to the surface of the substrate after the 3Drelief has been formed.
 6. The method of claim 1, wherein the machinelearning model is trained to generate the control commands to: configurethe digital inkjet printer to apply color ink to the surface of thesubstrate after the 3D relief has been formed.
 7. The method of claim 1,wherein the machine learning model is trained to generate the controlcommands to: configure an automated kiln to fire the substrate after the3D relief has been formed to produce a ceramic tile.
 8. A systemcomprising: one or more processors; and a non-transitory,computer-readable storage medium comprising instructions recordedthereon that, when executed by at least one processor of the system,cause the system to: receive information defining a relief pattern forforming a three-dimensional (3D) relief on a substrate; extract, fromthe information, a feature vector comprising one or more featuresdescribing the 3D relief; generate, using a machine learning model,control commands based on the feature vector, wherein the machinelearning model is trained, based on parameters associated with forming3D reliefs in substrates, to generate the control commands to: configurea digital inkjet printer to apply binder ink to a first region of asurface of the substrate, wherein the applied binder ink is configuredto form a protective layer over the first region of the surface of thesubstrate; and configure a mechanical brusher to brush the surface ofthe substrate to remove material from an unprotected second region ofthe surface of the substrate, wherein removing the material from theunprotected second region of the surface of the substrate forms agradient 3D relief; and send the control commands to the digital inkjetprinter to form the 3D relief on the substrate based on the reliefpattern.
 9. The system of claim 8, wherein the machine learning model istrained to generate the control commands to: configure the digitalinkjet printer to apply solvent ink to the surface of the substrateafter applying the binder ink to the first region of the surface of thesubstrate and before brushing the surface of the substrate.
 10. Thesystem of claim 8, wherein the parameters include a material type of thesubstrate or dimensions of the substrate.
 11. The system of claim 8,wherein the parameters include a depth of the 3D relief or a gradient ofthe 3D relief.
 12. The system of claim 8, wherein the parametersdescribe at least one of a glazing process, a color printing process, ora firing process.
 13. The system of claim 8, wherein the substrateincludes at least one of polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), acrylonitrile butadiene styrene (ABS), or luxuryvinyl tile (LVT).
 14. The system of claim 8, wherein the informationincludes a digital image.
 15. A non-transitory, computer-readablestorage medium comprising instructions recorded thereon that, whenexecuted by at least one processor of an automated production system,cause the automated production system to: receive a polychrome imagedefining a relief pattern for forming a three-dimensional (3D) relief ona substrate; extract, from the polychrome image, a feature vectorcomprising one or more features describing the 3D relief; generate,using a machine learning model, control commands based on the featurevector, wherein the machine learning model is trained, based onparameters describing types of 3D reliefs or types of substrates, togenerate the control commands to: cause a digital inkjet printer toapply binder ink to a first region of a surface of the substrate,wherein the applied binder ink is configured to form a protective layerover the first region of the surface of the substrate; and cause amechanical brusher to brush the surface of the substrate to removematerial from an unprotected second region of the surface of thesubstrate, wherein removing the material from the unprotected secondregion of the surface of the substrate forms a gradient 3D relief basedon the relief pattern.
 16. The non-transitory, computer-readable storagemedium of claim 15, wherein the machine learning model is trained togenerate the control commands to: cause the digital inkjet printer toapply solvent ink to the surface of the substrate after applying thebinder ink to the first region of the surface of the substrate andbefore brushing the surface of the substrate, wherein applying thesolvent ink causes at least some of the binder ink to sink into thesurface of the substrate such that the protective layer formed by thebinder ink is at a gradient depth relative to the surface of thesubstrate.
 17. The non-transitory, computer-readable storage medium ofclaim 15, wherein the parameters include a material type of thesubstrate or dimensions of the substrate.
 18. The non-transitory,computer-readable storage medium of claim 15, wherein the parametersinclude a depth of the 3D relief or a gradient of the 3D relief.
 19. Thenon-transitory, computer-readable storage medium of claim 15, whereinthe machine learning model is trained to generate the control commandsto: configure the digital inkjet printer to apply color ink to thesurface of the substrate after the 3D relief has been formed.
 20. Thenon-transitory, computer-readable storage medium of claim 15, whereinthe machine learning model is trained to generate the control commandsto: cause a glazing apparatus to apply glaze to the surface of thesubstrate after the 3D relief has been formed.